Winding configuration for inductive position encoder

Abstract

An electronic position encoder is provided including a scale, a detector and a signal processing configuration. The scale extends along an x-axis direction and includes a signal modulating scale pattern. The detector includes sensing elements and a field generating coil that surrounds an interior coil area. The field generating coil includes first and second elongated portions that each extend along the x-axis direction, connected by an end portion. The elongated portions have a nominal generating trace width dimension along the y-axis direction that is at least 0.1 times the nominal interior coil area width dimension in various embodiments. In various implementations, a conductive shield region of the detector may reduce the effect of a shielded end section of the end portion of the field generating coil on the sensing elements. The shielded end section may be located on a different PCB layer than the elongated portions.

Description

BACKGROUNDTechnical Field[0001]This disclosure relates to measurement instruments, and more particularly to inductive position encoders that may be utilized in precision measurement instruments.Description of the Related Art[0002]Various encoder configurations may include various types of optical, capacitive, magnetic, inductive, movement and / or position transducers. These transducers use various geometric configurations of a transmitter and a receiver in a read head to measure movement between the read head and a scale. Magnetic and inductive transducers are relatively robust to contamination, but not perfectly so.[0003]U.S. Pat. No. 6,011,389 (the '389 patent) describes an induced current position transducer usable in high accuracy applications, U.S. Pat. No. 5,973,494 (the '494 patent) and U.S. Pat. No. 6,002,250 (the '250 patent) describe incremental position inductive calipers and linear scales, including signal generating and processing circuits, and U.S. Pat. No. 5,886,519 (t...

AI Technical Summary

Problems solved by technology

Magnetic and inductive transducers are relatively robust to contamination, but not perfectly so.

However, such systems may be limited in their ability to provide certain combinations of features desired by users, such as combinations of compact size, high resolution, cost, robustness to contamination, etc.

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